<?php
namespace Think\Upload\Driver\Bcs;
use Think\Upload\Driver\Bcs\BCS_MimeTypes;
use Think\Upload\Driver\Bcs\BCS_RequestCore;
use Think\Upload\Driver\Bcs\BCS_ResponseCore;

if (! defined ( 'BCS_API_PATH' )) {
    define ( 'BCS_API_PATH', dirname ( __FILE__ ) );
}

//AK 公钥
define ( 'BCS_AK', '' );
//SK 私钥
define ( 'BCS_SK', '' );
//superfile 每个object分片后缀
define ( 'BCS_SUPERFILE_POSTFIX', '_bcs_superfile_' );
//sdk superfile分片大小 ，单位 B（字节）
define ( 'BCS_SUPERFILE_SLICE_SIZE', 1024 * 1024 );

require_once (BCS_API_PATH . '/requestcore.class.php');
require_once (BCS_API_PATH . '/mimetypes.class.php');
/**
 * Default BCS Exception.
 */
class BCS_Exception extends \Exception {
}
/**
 * BCS API
 */
class BaiduBCS {
    /*%******************************************************************************************%*/
    // CLASS CONSTANTS
    //百度云存储默认外网域名
    const DEFAULT_URL = 'bcs.duapp.com';
    //SDK 版本
    const API_VERSION = '2012-4-17-1.0.1.6';
    const ACL = 'acl';
    const BUCKET = 'bucket';
    const OBJECT = 'object';
    const HEADERS = 'headers';
    const METHOD = 'method';
    const AK = 'ak';
    const SK = 'sk';
    const QUERY_STRING = "query_string";
    const IMPORT_BCS_LOG_METHOD = "import_bs_log_method";
    const IMPORT_BCS_PRE_FILTER = "import_bs_pre_filter";
    const IMPORT_BCS_POST_FILTER = "import_bs_post_filter";
    /**********************************************************
     ******************* Policy Constants**********************
     **********************************************************/
    const STATEMETS = 'statements';
    //Action 用户动作
    //'*'代表所有action
    const BCS_SDK_ACL_ACTION_ALL = '*';
    //与bucket相关的action
    const BCS_SDK_ACL_ACTION_LIST_OBJECT = 'list_object';
    const BCS_SDK_ACL_ACTION_PUT_BUCKET_POLICY = 'put_bucket_policy';
    const BCS_SDK_ACL_ACTION_GET_BUCKET_POLICY = 'get_bucket_policy';
    const BCS_SDK_ACL_ACTION_DELETE_BUCKET = 'delete_bucket';
    //与object相关的action
    const BCS_SDK_ACL_ACTION_GET_OBJECT = 'get_object';
    const BCS_SDK_ACL_ACTION_PUT_OBJECT = 'put_object';
    const BCS_SDK_ACL_ACTION_DELETE_OBJECT = 'delete_object';
    const BCS_SDK_ACL_ACTION_PUT_OBJECT_POLICY = 'put_object_policy';
    const BCS_SDK_ACL_ACTION_GET_OBJECT_POLICY = 'get_object_policy';
    static $ACL_ACTIONS = array (
            self::BCS_SDK_ACL_ACTION_ALL,
            self::BCS_SDK_ACL_ACTION_LIST_OBJECT,
            self::BCS_SDK_ACL_ACTION_PUT_BUCKET_POLICY,
            self::BCS_SDK_ACL_ACTION_GET_BUCKET_POLICY,
            self::BCS_SDK_ACL_ACTION_DELETE_BUCKET,
            self::BCS_SDK_ACL_ACTION_GET_OBJECT,
            self::BCS_SDK_ACL_ACTION_PUT_OBJECT,
            self::BCS_SDK_ACL_ACTION_DELETE_OBJECT,
            self::BCS_SDK_ACL_ACTION_PUT_OBJECT_POLICY,
            self::BCS_SDK_ACL_ACTION_GET_OBJECT_POLICY );
    //EFFECT:
    const BCS_SDK_ACL_EFFECT_ALLOW = "allow";
    const BCS_SDK_ACL_EFFECT_DENY = "deny";
    static $ACL_EFFECTS = array (
            self::BCS_SDK_ACL_EFFECT_ALLOW,
            self::BCS_SDK_ACL_EFFECT_DENY );
    //ACL_TYPE:
    //公开读权限
    const BCS_SDK_ACL_TYPE_PUBLIC_READ = "public-read";
    //公开写权限（不具备删除权限）
    const BCS_SDK_ACL_TYPE_PUBLIC_WRITE = "public-write";
    //公开读写权限（不具备删除权限）
    const BCS_SDK_ACL_TYPE_PUBLIC_READ_WRITE = "public-read-write";
    //公开所有权限
    const BCS_SDK_ACL_TYPE_PUBLIC_CONTROL = "public-control";
    //私有权限，仅bucket所有者具有所有权限
    const BCS_SDK_ACL_TYPE_PRIVATE = "private";
    //SDK中开放此上五种acl_tpe
    static $ACL_TYPES = array (
            self::BCS_SDK_ACL_TYPE_PUBLIC_READ,
            self::BCS_SDK_ACL_TYPE_PUBLIC_WRITE,
            self::BCS_SDK_ACL_TYPE_PUBLIC_READ_WRITE,
            self::BCS_SDK_ACL_TYPE_PUBLIC_CONTROL,
            self::BCS_SDK_ACL_TYPE_PRIVATE );
    /*%******************************************************************************************%*/
    // PROPERTIES
    //是否使用ssl
    protected $use_ssl = false;
    //公钥 account key
    private $ak;
    //私钥 secret key
    private $sk;
    //云存储server地址
    private $hostname;

    /**
     * 构造函数
     * @param string $ak  云存储公钥
     * @param string $sk  云存储私钥
     * @param string $hostname 云存储Api访问地址
     * @throws BCS_Exception
     */
    public function __construct($ak = NULL, $sk = NULL, $hostname = NULL) {
        //valid ak & sk
        if (! $ak && ! defined ( 'BCS_AK' ) && false === getenv ( 'HTTP_BAE_ENV_AK' )) {
            throw new BCS_Exception ( 'No account key was passed into the constructor.' );
        }
        if (! $sk && ! defined ( 'BCS_SK' ) && false === getenv ( 'HTTP_BAE_ENV_SK' )) {
            throw new BCS_Exception ( 'No secret key was passed into the constructor.' );
        }
        if ($ak && $sk) {
            $this->ak = $ak;
            $this->sk = $sk;
        } elseif (defined ( 'BCS_AK' ) && defined ( 'BCS_SK' ) && strlen ( BCS_AK ) > 0 && strlen ( BCS_SK ) > 0) {
            $this->ak = BCS_AK;
            $this->sk = BCS_SK;
        } elseif (false !== getenv ( 'HTTP_BAE_ENV_AK' ) && false !== getenv ( 'HTTP_BAE_ENV_SK' )) {
            $this->ak = getenv ( 'HTTP_BAE_ENV_AK' );
            $this->sk = getenv ( 'HTTP_BAE_ENV_SK' );
        } else {
            throw new BCS_Exception ( 'Construct can not get ak &sk pair, please check!' );
        }
        //valid $hostname
        if (NULL !== $hostname) {
            $this->hostname = $hostname;
        } elseif (false !== getenv ( 'HTTP_BAE_ENV_ADDR_BCS' )) {
            $this->hostname = getenv ( 'HTTP_BAE_ENV_ADDR_BCS' );
        } else {
            $this->hostname = self::DEFAULT_URL;
        }
    }

    /**
     * 将消息发往Baidu BCS.
     * @param array $opt
     * @return BCS_ResponseCore
     */
    private function authenticate($opt) {
        //set common param into opt
        $opt [self::AK] = $this->ak;
        $opt [self::SK] = $this->sk;

        // Validate the S3 bucket name, only list_bucket didnot need validate_bucket
        if (! ('/' == $opt [self::OBJECT] && '' == $opt [self::BUCKET] && 'GET' == $opt [self::METHOD] && ! isset ( $opt [self::QUERY_STRING] [self::ACL] )) && ! self::validate_bucket ( $opt [self::BUCKET] )) {
            throw new BCS_Exception ( $opt [self::BUCKET] . 'is not valid, please check!' );
        }
        //Validate object
        if (isset ( $opt [self::OBJECT] ) && ! self::validate_object ( $opt [self::OBJECT] )) {
            throw new BCS_Exception ( "Invalid object param[" . $opt [self::OBJECT] . "], please check.", - 1 );
        }
        //construct url
        $url = $this->format_url ( $opt );
        if ($url === false) {
            throw new BCS_Exception ( 'Can not format url, please check your param!', - 1 );
        }
        $opt ['url'] = $url;
        $this->log ( "[method:" . $opt [self::METHOD] . "][url:$url]", $opt );
        //build request
        $request = new BCS_RequestCore ( $opt ['url'] );
        $headers = array (
                'Content-Type' => 'application/x-www-form-urlencoded' );

        $request->set_method ( $opt [self::METHOD] );
        //Write get_object content to fileWriteTo
        if (isset ( $opt ['fileWriteTo'] )) {
            $request->set_write_file ( $opt ['fileWriteTo'] );
        }
        // Merge the HTTP headers
        if (isset ( $opt [self::HEADERS] )) {
            $headers = array_merge ( $headers, $opt [self::HEADERS] );
        }
        // Set content to Http-Body
        if (isset ( $opt ['content'] )) {
            $request->set_body ( $opt ['content'] );
        }
        // Upload file
        if (isset ( $opt ['fileUpload'] )) {
            if (! file_exists ( $opt ['fileUpload'] )) {
                throw new BCS_Exception ( 'File[' . $opt ['fileUpload'] . '] not found!', - 1 );
            }
            $request->set_read_file ( $opt ['fileUpload'] );
            // Determine the length to read from the file
            $length = $request->read_stream_size; // The file size by default
            $file_size = $length;
            if (isset ( $opt ["length"] )) {
                if ($opt ["length"] > $file_size) {
                    throw new BCS_Exception ( "Input opt[length] invalid! It can not bigger than file-size", - 1 );
                }
                $length = $opt ['length'];
            }
            if (isset ( $opt ['seekTo'] ) && ! isset ( $opt ["length"] )) {
                // Read from seekTo until EOF by default, when set seekTo but not set $opt["length"]
                $length -= ( integer ) $opt ['seekTo'];
            }
            $request->set_read_stream_size ( $length );
            // Attempt to guess the correct mime-type
            if ($headers ['Content-Type'] === 'application/x-www-form-urlencoded') {
                $extension = explode ( '.', $opt ['fileUpload'] );
                $extension = array_pop ( $extension );
                $mime_type = BCS_MimeTypes::get_mimetype ( $extension );
                $headers ['Content-Type'] = $mime_type;
            }
            $headers ['Content-MD5'] = '';
        }
        // Handle streaming file offsets
        if (isset ( $opt ['seekTo'] )) {
            // Pass the seek position to BCS_RequestCore
            $request->set_seek_position ( ( integer ) $opt ['seekTo'] );
        }
        // Add headers to request and compute the string to sign
        foreach ( $headers as $header_key => $header_value ) {
            // Strip linebreaks from header values as they're illegal and can allow for security issues
            $header_value = str_replace ( array (
                    "\r",
                    "\n" ), '', $header_value );
            // Add the header if it has a value
            if ($header_value !== '') {
                $request->add_header ( $header_key, $header_value );
            }
        }
        // Set the curl options.
        if (isset ( $opt ['curlopts'] ) && count ( $opt ['curlopts'] )) {
            $request->set_curlopts ( $opt ['curlopts'] );
        }
        $request->send_request ();
        require_once(dirname(__FILE__). "/requestcore.class.php");
        return new BCS_ResponseCore ( $request->get_response_header (), $request->get_response_body (), $request->get_response_code () );
    }

    /**
     * 获取当前密钥对拥有者的bucket列表
     * @param array $opt (Optional)
     * BaiduBCS::IMPORT_BCS_LOG_METHOD - String - Optional: 支持用户传入日志处理函数，函数定义如 function f($log)
     * @throws BCS_Exception
     * @return BCS_ResponseCore
     */
    public function list_bucket($opt = array()) {
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = '';
        $opt [self::METHOD] = 'GET';
        $opt [self::OBJECT] = '/';
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "List bucket success!" : "List bucket failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 创建 bucket
     * @param string $bucket (Required) bucket名称
     * @param string $acl (Optional)    bucket权限设置，若为null，使用server分配的默认权限
     * @param array $opt (Optional)
     * @throws BCS_Exception
     * @return BCS_ResponseCore
     */
    public function create_bucket($bucket, $acl = NULL, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = $bucket;
        $opt [self::METHOD] = 'PUT';
        $opt [self::OBJECT] = '/';
        if (NULL !== $acl) {
            if (! in_array ( $acl, self::$ACL_TYPES )) {
                throw new BCS_Exception ( "Invalid acl_type[" . $acl . "], please check!", - 1 );
            }
            self::set_header_into_opt ( "x-bs-acl", $acl, $opt );
        }
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Create bucket success!" : "Create bucket failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 删除bucket
     * @param string $bucket (Required)
     * @param array $opt (Optional)
     * @return boolean|BCS_ResponseCore
     */
    public function delete_bucket($bucket, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = $bucket;
        $opt [self::METHOD] = 'DELETE';
        $opt [self::OBJECT] = '/';
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Delete bucket success!" : "Delete bucket failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 设置bucket的acl，有三种模式，
     * (1).设置详细json格式的acl；
     * a. $acl 为json的array
     * b. $acl 为json的string
     * (2).通过acl_type字段进行设置
     * a. $acl 为BaiduBCS::$ACL_TYPES中的字段
     * @param string $bucket (Required)
     * @param string $acl (Required)
     * @param array $opt (Optional)
     * @return boolean|BCS_ResponseCore
     */
    public function set_bucket_acl($bucket, $acl, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $result = $this->analyze_user_acl ( $acl );
        $opt = array_merge ( $opt, $result );
        $opt [self::BUCKET] = $bucket;
        $opt [self::METHOD] = 'PUT';
        $opt [self::OBJECT] = '/';
        $opt [self::QUERY_STRING] = array (
                self::ACL => 1 );
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Set bucket acl success!" : "Set bucket acl failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 获取bucket的acl
     * @param string $bucket (Required)
     * @param array $opt (Optional)
     * @return BCS_ResponseCore
     */
    public function get_bucket_acl($bucket, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = $bucket;
        $opt [self::METHOD] = 'GET';
        $opt [self::OBJECT] = '/';
        $opt [self::QUERY_STRING] = array (
                self::ACL => 1 );
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Get bucket acl success!" : "Get bucket acl failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 获取bucket中object列表
     * @param string $bucket (Required)
     * @param array $opt (Optional)
     * start : 主要用于翻页功能，用法同mysql中start的用法
     * limit : 主要用于翻页功能，用法同mysql中limit的用法
     * prefix: 只返回以prefix为前缀的object，此处prefix必须以'/'开头
     * @throws BCS_Exception
     * @return BCS_ResponseCore
     */
    public function list_object($bucket, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = $bucket;
        if (empty ( $opt [self::BUCKET] )) {
            throw new BCS_Exception ( "Bucket should not be empty, please check", - 1 );
        }
        $opt [self::METHOD] = 'GET';
        $opt [self::OBJECT] = '/';
        $opt [self::QUERY_STRING] = array ();
        if (isset ( $opt ['start'] ) && is_int ( $opt ['start'] )) {
            $opt [self::QUERY_STRING] ['start'] = $opt ['start'];
        }
        if (isset ( $opt ['limit'] ) && is_int ( $opt ['limit'] )) {
            $opt [self::QUERY_STRING] ['limit'] = $opt ['limit'];
        }
        if (isset ( $opt ['prefix'] )) {
            $opt [self::QUERY_STRING] ['prefix'] = rawurlencode ( $opt ['prefix'] );
        }
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "List object success!" : "Lit object failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 以目录形式获取bucket中object列表
     * @param string $bucket (Required)
     * @param $dir (Required)
     * 目录名，格式为必须以'/'开头和结尾，默认为'/'
     * @param string $list_model (Required)
     * 目录展现形式，值可以为0,1,2，默认为2，以下对各个值的功能进行介绍：
     * 0->只返回object列表，不返回子目录列表
     * 1->只返回子目录列表，不返回object列表
     * 2->同时返回子目录列表和object列表
     * @param array $opt (Optional)
     * start : 主要用于翻页功能，用法同mysql中start的用法
     * limit : 主要用于翻页功能，用法同mysql中limit的用法
     * @throws BCS_Exception
     * @return BCS_ResponseCore
     */
    public function list_object_by_dir($bucket, $dir = '/', $list_model = 2, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = $bucket;
        if (empty ( $opt [self::BUCKET] )) {
            throw new BCS_Exception ( "Bucket should not be empty, please check", - 1 );
        }
        $opt [self::METHOD] = 'GET';
        $opt [self::OBJECT] = '/';
        $opt [self::QUERY_STRING] = array ();
        if (isset ( $opt ['start'] ) && is_int ( $opt ['start'] )) {
            $opt [self::QUERY_STRING] ['start'] = $opt ['start'];
        }
        if (isset ( $opt ['limit'] ) && is_int ( $opt ['limit'] )) {
            $opt [self::QUERY_STRING] ['limit'] = $opt ['limit'];
        }

        $opt [self::QUERY_STRING] ['prefix'] = rawurlencode ( $dir );
        $opt [self::QUERY_STRING] ['dir'] = $list_model;

        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "List object success!" : "Lit object failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 上传文件
     * @param string $bucket (Required)
     * @param string $object (Required)
     * @param string $file (Required); 需要上传的文件的文件路径
     * @param array $opt (Optional)
     * filename - Optional; 指定文件名
     * acl - Optional ; 上传文件的acl，只能使用acl_type
     * seekTo - Optional; 上传文件的偏移位置
     * length - Optional; 待上传长度
     * @return BCS_ResponseCore
     */
    public function create_object($bucket, $object, $file, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = $bucket;
        $opt [self::OBJECT] = $object;
        $opt ['fileUpload'] = $file;
        $opt [self::METHOD] = 'PUT';
        if (isset ( $opt ['acl'] )) {
            if (in_array ( $opt ['acl'], self::$ACL_TYPES )) {
                self::set_header_into_opt ( "x-bs-acl", $opt ['acl'], $opt );
            } else {
                throw new BCS_Exception ( "Invalid acl string, it should be acl_type", - 1 );
            }
            unset ( $opt ['acl'] );
        }
        if (isset ( $opt ['filename'] )) {
            self::set_header_into_opt ( "Content-Disposition", 'attachment; filename=' . $opt ['filename'], $opt );
        }
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Create object[$object] file[$file] success!" : "Create object[$object] file[$file] failed! Response: [" . $response->body . "] Logid[" . $response->header ["x-bs-request-id"] . "]", $opt );
        return $response;
    }

    /**
     * 上传文件
     * @param string $bucket (Required)
     * @param string $object (Required)
     * @param string $file (Required); 需要上传的文件的文件路径
     * @param array $opt (Optional)
     * filename - Optional; 指定文件名
     * acl - Optional ; 上传文件的acl，只能使用acl_type
     * @return BCS_ResponseCore
     */
    public function create_object_by_content($bucket, $object, $content, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = $bucket;
        $opt [self::OBJECT] = $object;
        $opt [self::METHOD] = 'PUT';
        if ($content !== NULL && is_string ( $content )) {
            $opt ['content'] = $content;
        } else {
            throw new BCS_Exception ( "Invalid object content, please check.", - 1 );
        }
        if (isset ( $opt ['acl'] )) {
            if (in_array ( $opt ['acl'], self::$ACL_TYPES )) {
                self::set_header_into_opt ( "x-bs-acl", $opt ['acl'], $opt );
            } else {
                throw new BCS_Exception ( "Invalid acl string, it should be acl_type", - 1 );
            }
            unset ( $opt ['acl'] );
        }
        if (isset ( $opt ['filename'] )) {
            self::set_header_into_opt ( "Content-Disposition", 'attachment; filename=' . $opt ['filename'], $opt );
        }
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Create object[$object] success!" : "Create object[$object] failed! Response: [" . $response->body . "] Logid[" . $response->header ["x-bs-request-id"] . "]", $opt );
        return $response;
    }

    /**
     * 通过superfile的方式上传文件
     * @param string $bucket (Required)
     * @param string $object (Required)
     * @param string $file (Required); 需要上传的文件的文件路径
     * @param array $opt (Optional)
     * filename - Optional; 指定文件名
     * sub_object_size - Optional; 指定子文件的划分大小，单位B，建议以256KB为单位进行子object划分，默认为1MB进行划分
     * @return BCS_ResponseCore
     */
    public function create_object_superfile($bucket, $object, $file, $opt = array()) {
        if (isset ( $opt ['length'] ) || isset ( $opt ['seekTo'] )) {
            throw new BCS_Exception ( "Temporary unsupport opt of length and seekTo of superfile.", - 1 );
        }
        //$opt array
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = $bucket;
        $opt ['fileUpload'] = $file;
        $opt [self::METHOD] = 'PUT';
        if (isset ( $opt ['acl'] )) {
            if (in_array ( $opt ['acl'], self::$ACL_TYPES )) {
                self::set_header_into_opt ( "x-bs-acl", $opt ['acl'], $opt );
            } else {
                throw new BCS_Exception ( "Invalid acl string, it should be acl_type", - 1 );
            }
            unset ( $opt ['acl'] );
        }
        //切片上传
        if (! file_exists ( $opt ['fileUpload'] )) {
            throw new BCS_Exception ( 'File not found!', - 1 );
        }
        $fileSize = filesize ( $opt ['fileUpload'] );
        $sub_object_size = 1024 * 1024; //default 1MB
        if (defined ( "BCS_SUPERFILE_SLICE_SIZE" )) {
            $sub_object_size = BCS_SUPERFILE_SLICE_SIZE;
        }
        if (isset ( $opt ["sub_object_size"] )) {
            if (is_int ( $opt ["sub_object_size"] ) && $opt ["sub_object_size"] > 0) {
                $sub_object_size = $opt ["sub_object_size"];
            } else {
                throw new BCS_Exception ( "Param [sub_object_size] invalid ,please check!", - 1 );
            }
        }
        $sliceNum = intval ( ceil ( $fileSize / $sub_object_size ) );
        $this->log ( "File[" . $opt ['fileUpload'] . "], size=[$fileSize], sub_object_size=[$sub_object_size], sub_object_num=[$sliceNum]", $opt );
        $object_list = array (
                'object_list' => array () );
        for($i = 0; $i < $sliceNum; $i ++) {
            //send slice
            $opt ['seekTo'] = $i * $sub_object_size;

            if (($i + 1) === $sliceNum) {
                //last sub object
                $opt ['length'] = (0 === $fileSize % $sub_object_size) ? $sub_object_size : $fileSize % $sub_object_size;
            } else {
                $opt ['length'] = $sub_object_size;
            }
            $opt [self::OBJECT] = $object . BCS_SUPERFILE_POSTFIX . $i;
            $object_list ['object_list'] ['part_' . $i] = array ();
            $object_list ['object_list'] ['part_' . $i] ['url'] = 'bs://' . $bucket . $opt [self::OBJECT];
            $this->log ( "Begin to upload Sub-object[" . $opt [self::OBJECT] . "][$i/$sliceNum][seekto:" . $opt ['seekTo'] . "][Length:" . $opt ['length'] . "]", $opt );
            $response = $this->create_object ( $bucket, $opt [self::OBJECT], $file, $opt );
            if ($response->isOK ()) {
                $this->log ( "Sub-object upload[" . $opt [self::OBJECT] . "][$i/$sliceNum][seekto:" . $opt ['seekTo'] . "][Length:" . $opt ['length'] . "]success! ", $opt );
                $object_list ['object_list'] ['part_' . $i] ['etag'] = $response->header ['Content-MD5'];
                continue;
            } else {
                $this->log ( "Sub-object upload[" . $opt [self::OBJECT] . "][$i/$sliceNum] failed! ", $opt );
                return $response;
            }
        }
        //将子文件分片的列表构造成 superfile
        unset ( $opt ['fileUpload'] );
        unset ( $opt ['length'] );
        unset ( $opt ['seekTo'] );
        $opt ['content'] = self::array_to_json ( $object_list );
        $opt [self::QUERY_STRING] = array (
                "superfile" => 1 );
        $opt [self::OBJECT] = $object;
        if (isset ( $opt ['filename'] )) {
            self::set_header_into_opt ( "Content-Disposition", 'attachment; filename=' . $opt ['filename'], $opt );
        }
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Create object-superfile success!" : "Create object-superfile failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 将目录中的所有文件进行上传，每个文件为单独object，object命名方式下详：
     * 如有 /home/worker/a/b/c.txt  需上传目录为$dir=/home/worker/a
     * object命令方式为
     * 1. object默认命名方式为 “子目录名 +文件名”，如上述文件c.txt，默认为 '/b/c.txt'
     * 2. 增强命名模式，在$opt中有可选参数进行配置
     * 举例说明 ：prefix . has_sub_directory?"/b":"" . '/c.txt'
     * @param string $bucket (Required)
     * @param string $dir (Required)
     * @param array $opt(Optional)
     * string prefix 文件object前缀
     * boolean has_sub_directory(default=true)   object命名中是否携带文件的子目录结构，若置为false，请确认待上传的目录和所有子目录中没有重名文件，否则会产生object覆盖问题
     * BaiduBCS::IMPORT_BCS_PRE_FILTER   用户可自定义上传文件前的操作函数
     * 1. 函数参数列表顺序需为 ($bucket,$object,$file,&$opt)，注意$opt为upload_directory函数传入的$opt的拷贝，只对当前object生效
     * 2. 函数返回值必须为boolean，当true该文件进行上传，若false跳过上传
     * 3. 如果函数返回false，将不会进行post_filter的调用
     * BaiduBCS::IMPORT_BCS_POST_FILTER  用户可自定义上传文件后的操作函数
     * 1. 函数参数列表顺序需为 ($bucket,$object,$file,&$opt,$response)，注意$opt为upload_directory函数传入的$opt的拷贝，只对当前object生效
     * 2. 函数返回值无要求
     * string seek_object 用户断点续传，需要为object名称，如果该object在目录中不存在，抛出异常，若存在则将该object和此后的object进行上传
     * string seek_object_id 作用同seek_object，只需要传入上传过程中日志中展示的[a/b]中object序号即可，注意object序号是以1开始计算的
     * @return array  数组形式的上传结果
     * 'success' => int  上传成功的文件数目
     * 'skipped' => int  被跳过的文件
     * 'failed' => array()   上传失败的文件
     *
     */
    public function upload_directory($bucket, $dir, $opt = array()) {
        $this->assertParameterArray ( $opt );
        if (! is_dir ( $dir )) {
            throw new BCS_Exception ( "$dir is not a dir!", - 1 );
        }
        $result = array (
                "success" => 0,
                "failed" => array (),
                "skipped" => 0 );
        $prefix = "";
        if (isset ( $opt ['prefix'] )) {
            $prefix = $opt ['prefix'];
        }
        $has_sub_directory = true;
        if (isset ( $opt ['has_sub_directory'] ) && is_bool ( $opt ['has_sub_directory'] )) {
            $has_sub_directory = $opt ['has_sub_directory'];
        }
        //获取文件树和构造object名
        $file_tree = self::get_filetree ( $dir );
        $objects = array ();
        foreach ( $file_tree as $file ) {
            $object = $has_sub_directory == true ? substr ( $file, strlen ( $dir ) ) : "/" . basename ( $file );
            $objects [$prefix . $object] = $file;
        }
        $objectCount = count ( $objects );
        $before_upload_log = "Upload directory: bucket[$bucket] upload_dir[$dir] file_sum[$objectCount]";
        if (isset ( $opt ["seek_object_id"] )) {
            $before_upload_log .= " seek_object_id[" . $opt ["seek_object_id"] . "/$objectCount]";
        }
        if (isset ( $opt ["seek_object"] )) {
            $before_upload_log .= " seek_object[" . $opt ["seek_object"] . "]";
        }
        $this->log ( $before_upload_log, $opt );
        //查看是否需要查询断点，进行断点续传
        if (isset ( $opt ["seek_object_id"] ) && isset ( $opt ["seek_object"] )) {
            throw new BCS_Exception ( "Can not set see_object_id and seek_object at the same time!", - 1 );
        }

        $num = 1;
        if (isset ( $opt ["seek_object"] )) {
            if (isset ( $objects [$opt ["seek_object"]] )) {
                foreach ( $objects as $object => $file ) {
                    if ($object != $opt ["seek_object"]) {
                        //当非断点文件，该object已完成上传
                        $this->log ( "Seeking[" . $opt ["seek_object"] . "]. Skip id[$num/$objectCount]object[$object]file[$file].", $opt );
                        //$result ['skipped'] [] = "[$num/$objectCount]  " . $file;
                        $result ['skipped'] ++;
                        unset ( $objects [$object] );
                    } else {
                        //当找到断点文件，停止循环，从断点文件重新上传
                        //当非断点文件，该object已完成上传
                        $this->log ( "Found seek id[$num/$objectCount]object[$object]file[$file], begin from here.", $opt );
                        break;
                    }
                    $num ++;
                }
            } else {
                throw new BCS_Exception ( "Can not find you seek object, please check!", - 1 );
            }
        }
        if (isset ( $opt ["seek_object_id"] )) {
            if (is_int ( $opt ["seek_object_id"] ) && $opt ["seek_object_id"] <= $objectCount) {
                foreach ( $objects as $object => $file ) {
                    if ($num < $opt ["seek_object_id"]) {
                        $this->log ( "Seeking object of [" . $opt ["seek_object_id"] . "/$objectCount]. Skip  id[$num/$objectCount]object[$object]file[$file].", $opt );
                        //$result ['skipped'] [] = "[$num/$objectCount]  " . $file;
                        $result ['skipped'] ++;
                        unset ( $objects [$object] );
                    } else {
                        break;
                    }
                    $num ++;
                }
            } else {
                throw new BCS_Exception ( "Param seek_object_id not valid, please check!", - 1 );
            }
        }
        //上传objects
        $objectCount = count ( $objects );
        foreach ( $objects as $object => $file ) {
            $tmp_opt = array_merge ( $opt );
            if (isset ( $opt [self::IMPORT_BCS_PRE_FILTER] ) && function_exists ( $opt [self::IMPORT_BCS_PRE_FILTER] )) {
                $bolRes = $opt [self::IMPORT_BCS_PRE_FILTER] ( $bucket, $object, $file, $tmp_opt );
                if ($bolRes !== true) {
                    $this->log ( "User pre_filter_function return un-true. Skip id[$num/$objectCount]object[$object]file[$file].", $opt );
                    //$result ['skipped'] [] = "id[$num/$objectCount]object[$object]file[$file]";
                    $result ['skipped'] ++;
                    $num ++;
                    continue;
                }
            }
            try {
                $response = $this->create_object ( $bucket, $object, $file, $tmp_opt );
            } catch ( Exception $e ) {
                $this->log ( $e->getMessage (), $opt );
                $this->log ( "Upload Failed id[$num/$objectCount]object[$object]file[$file].", $opt );
                $num ++;
                continue;
            }
            if ($response->isOK ()) {
                $result ["success"] ++;
                $this->log ( "Upload Success id[$num/$objectCount]object[$object]file[$file].", $opt );
            } else {
                $result ["failed"] [] = "id[$num/$objectCount]object[$object]file[$file]";
                $this->log ( "Upload Failed id[$num/$objectCount]object[$object]file[$file].", $opt );
            }
            if (isset ( $opt [self::IMPORT_BCS_POST_FILTER] ) && function_exists ( $opt [self::IMPORT_BCS_POST_FILTER] )) {
                $opt [self::IMPORT_BCS_POST_FILTER] ( $bucket, $object, $file, $tmp_opt, $response );
            }
            $num ++;
        }
        //打印日志并返回结果数组
        $result_str = "\r\n\r\nUpload $dir to $bucket finished!\r\n";
        $result_str .= "**********************************************************\r\n";
        $result_str .= "**********************Result Summary**********************\r\n";
        $result_str .= "**********************************************************\r\n";
        $result_str .= "Upload directory :  [$dir]\r\n";
        $result_str .= "File num :  [$objectCount]\r\n";
        $result_str .= "Success: \r\n\tNum: " . $result ["success"] . "\r\n";
        $result_str .= "Skipped:\r\n\tNum:" . $result ["skipped"] . "\r\n";
        //        foreach ( $result ["skipped"] as $skip ) {
        //            $result_str .= "\t$skip\r\n";
        //        }
        $result_str .= "Failed:\r\n\tNum:" . count ( $result ["failed"] ) . "\r\n";
        foreach ( $result ["failed"] as $fail ) {
            $result_str .= "\t$fail\r\n";
        }
        if (isset ( $opt [self::IMPORT_BCS_LOG_METHOD] )) {
            $this->log ( $result_str, $opt );
        } else {
            echo $result_str;
        }
        return $result;
    }

    /**
     * 通过此方法以拷贝的方式创建object，object来源为$source
     * @param array $source (Required)  object 来源
     * bucket(Required)
     * object(Required)
     * @param array $dest (Required)    待拷贝的目标object
     * bucket(Required)
     * object(Required)
     * @param array $opt (Optional)
     * source_tag 指定拷贝对象的版本号
     * @throws BCS_Exception
     * @return BCS_ResponseCore
     */
    public function copy_object($source, $dest, $opt = array()) {
        $this->assertParameterArray ( $opt );
        //valid source and dest
        if (empty ( $source ) || ! is_array ( $source ) || ! isset ( $source [self::BUCKET] ) || ! isset ( $source [self::OBJECT] )) {
            throw new BCS_Exception ( '$source invalid, please check!', - 1 );
        }
        if (empty ( $dest ) || ! is_array ( $dest ) || ! isset ( $dest [self::BUCKET] ) || ! isset ( $dest [self::OBJECT] ) || ! self::validate_bucket ( $dest [self::BUCKET] ) || ! self::validate_object ( $dest [self::OBJECT] )) {
            throw new BCS_Exception ( '$dest invalid, please check!', - 1 );
        }
        $opt [self::BUCKET] = $dest [self::BUCKET];
        $opt [self::OBJECT] = $dest [self::OBJECT];
        $opt [self::METHOD] = 'PUT';
        self::set_header_into_opt ( 'x-bs-copy-source', 'bs://' . $source [self::BUCKET] . $source [self::OBJECT], $opt );
        if (isset ( $opt ['source_tag'] )) {
            self::set_header_into_opt ( 'x-bs-copy-source-tag', $opt ['source_tag'], $opt );
        }
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Copy object success!" : "Copy object failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 设置object的meta信息
     * @param string $bucket (Required)
     * @param string $object (Required)
     * @param array $opt (Optional)
     * 目前支持的meta信息如下：
     * Content-Type
     * Cache-Control
     * Content-Disposition
     * Content-Encoding
     * Content-MD5
     * Expires
     * @return BCS_ResponseCore
     */
    public function set_object_meta($bucket, $object, $meta, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $this->assertParameterArray ( $meta );
        $opt [self::BUCKET] = $bucket;
        $opt [self::OBJECT] = $object;
        $opt [self::METHOD] = 'PUT';
        //利用copy_object接口来设置meta信息
        $source = "bs://$bucket$object";
        if (empty ( $meta )) {
            throw new BCS_Exception ( '$meta can not be empty! And $meta must be array.', - 1 );
        }
        foreach ( $meta as $header => $value ) {
            self::set_header_into_opt ( $header, $value, $opt );
        }
        $source = array (
                self::BUCKET => $bucket,
                self::OBJECT => $object );
        $response = $this->copy_object ( $source, $source, $opt );
        $this->log ( $response->isOK () ? "Set object meta success!" : "Set object meta failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 获取object的acl
     * @param string $bucket (Required)
     * @param string $object (Required)
     * @param array $opt (Optional)
     * @throws BCS_Exception
     * @return BCS_ResponseCore
     */
    public function get_object_acl($bucket, $object, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = $bucket;
        $opt [self::METHOD] = 'GET';
        $opt [self::OBJECT] = $object;
        $opt [self::QUERY_STRING] = array (
                self::ACL => 1 );
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Get object acl success!" : "Get object acl failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 设置object的acl，有三种模式，
     * (1).设置详细json格式的acl；
     * a. $acl 为json的array
     * b. $acl 为json的string
     * (2).通过acl_type字段进行设置
     * a. $acl 为BaiduBCS::$ACL_ACTIONS中的字段
     * @param string $bucket (Required)
     * @param string $object (Required)
     * @param string|array $acl (Required)
     * @param array $opt (Optional)
     * @return BCS_ResponseCore
     */
    public function set_object_acl($bucket, $object, $acl, $opt = array()) {
        $this->assertParameterArray ( $opt );
        //analyze acl
        $result = $this->analyze_user_acl ( $acl );
        $opt = array_merge ( $opt, $result );
        $opt [self::BUCKET] = $bucket;
        $opt [self::METHOD] = 'PUT';
        $opt [self::OBJECT] = $object;
        $opt [self::QUERY_STRING] = array (
                self::ACL => 1 );
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Set object acl success!" : "Set object acl failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 删除object
     * @param string $bucket (Required)
     * @param string $object (Required)
     * @param array $opt (Optional)
     * @throws BCS_Exception
     * @return BCS_ResponseCore
     */
    public function delete_object($bucket, $object, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = $bucket;
        $opt [self::METHOD] = 'DELETE';
        $opt [self::OBJECT] = $object;
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Delete object success!" : "Delete object failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 判断object是否存在
     * @param string $bucket (Required)
     * @param string $object (Required)
     * @param array $opt (Optional)
     * @throws BCS_Exception
     * @return boolean true|boolean false|BCS_ResponseCore
     * true：object存在
     * false：不存在
     * BCS_ResponseCore其他错误
     */
    public function is_object_exist($bucket, $object, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = $bucket;
        $opt [self::METHOD] = 'HEAD';
        $opt [self::OBJECT] = $object;
        $response = $this->get_object_info ( $bucket, $object, $opt );
        if ($response->isOK ()) {
            return true;
        } elseif ($response->status === 404) {
            return false;
        }
        return $response;
    }

    /**
     * 获取文件信息，发送的为HTTP HEAD请求，文件信息都在http response的header中，不会提取文件的内容
     * @param string $bucket (Required)
     * @param string $object (Required)
     * @param array $opt (Optional)
     * @throws BCS_Exception
     * @return array BCS_ResponseCore
     */
    public function get_object_info($bucket, $object, $opt = array()) {
        $this->assertParameterArray ( $opt );
        $opt [self::BUCKET] = $bucket;
        $opt [self::METHOD] = 'HEAD';
        $opt [self::OBJECT] = $object;
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Get object info success!" : "Get object info failed! Response: [" . $response->body . "]", $opt );
        return $response;
    }

    /**
     * 下载object
     * @param string $bucket (Required)
     * @param string $object (Required)
     * @param array $opt (Optional)
     * fileWriteTo   (Optional)直接将请求结果写入该文件，如果fileWriteTo文件存在，sdk进行重命名再存储
     * @throws BCS_Exception
     * @return BCS_ResponseCore
     */
    public function get_object($bucket, $object, $opt = array()) {
        $this->assertParameterArray ( $opt );
        //若fileWriteTo待写入的文件已经存在，需要进行重命名
        if (isset ( $opt ["fileWriteTo"] ) && file_exists ( $opt ["fileWriteTo"] )) {
            $original_file_write_to = $opt ["fileWriteTo"];
            $arr = explode ( DIRECTORY_SEPARATOR, $opt ["fileWriteTo"] );
            $file_name = $arr [count ( $arr ) - 1];
            $num = 1;
            while ( file_exists ( $opt ["fileWriteTo"] ) ) {
                $new_name_arr = explode ( ".", $file_name );
                if (count ( $new_name_arr ) > 1) {
                    $new_name_arr [count ( $new_name_arr ) - 2] .= " ($num)";
                } else {
                    $new_name_arr [0] .= " ($num)";
                }
                $arr [count ( $arr ) - 1] = implode ( ".", $new_name_arr );
                $opt ["fileWriteTo"] = implode ( DIRECTORY_SEPARATOR, $arr );
                $num ++;
            }
            $this->log ( "[$original_file_write_to] already exist, rename it to [" . $opt ["fileWriteTo"] . "]", $opt );
        }
        $opt [self::BUCKET] = $bucket;
        $opt [self::METHOD] = 'GET';
        $opt [self::OBJECT] = $object;
        $response = $this->authenticate ( $opt );
        $this->log ( $response->isOK () ? "Get object success!" : "Get object failed! Response: [" . $response->body . "]", $opt );
        if (! $response->isOK () && isset ( $opt ["fileWriteTo"] )) {
            unlink ( $opt ["fileWriteTo"] );
        }
        return $response;
    }

    /**
     * 生成签名链接
     */
    private function generate_user_url($method, $bucket, $object, $opt = array()) {
        $opt [self::AK] = $this->ak;
        $opt [self::SK] = $this->sk;
        $opt [self::BUCKET] = $bucket;
        $opt [self::METHOD] = $method;
        $opt [self::OBJECT] = $object;
        $opt [self::QUERY_STRING] = array ();
        if (isset ( $opt ["time"] )) {
            $opt [self::QUERY_STRING] ["time"] = $opt ["time"];
        }
        if (isset ( $opt ["size"] )) {
            $opt [self::QUERY_STRING] ["size"] = $opt ["size"];
        }
        return $this->format_url ( $opt );
    }

    /**
     * 生成get_object的url
     * @param string $bucket (Required)
     * @param string $object (Required)
     * return false| string url
     */
    public function generate_get_object_url($bucket, $object, $opt = array()) {
        $this->assertParameterArray ( $opt );
        return $this->generate_user_url ( "GET", $bucket, $object, $opt );
    }

    /**
     * 生成put_object的url
     * @param string $bucket (Required)
     * @param string $object (Required)
     * return false| string url
     */
    public function generate_put_object_url($bucket, $object, $opt = array()) {
        $this->assertParameterArray ( $opt );
        return $this->generate_user_url ( "PUT", $bucket, $object, $opt );
    }

    /**
     * 生成post_object的url
     * @param string $bucket (Required)
     * @param string $object (Required)
     * return false| string url
     */
    public function generate_post_object_url($bucket, $object, $opt = array()) {
        $this->assertParameterArray ( $opt );
        return $this->generate_user_url ( "POST", $bucket, $object, $opt );
    }

    /**
     * 生成delete_object的url
     * @param string $bucket (Required)
     * @param string $object (Required)
     * return false| string url
     */
    public function generate_delete_object_url($bucket, $object, $opt = array()) {
        $this->assertParameterArray ( $opt );
        return $this->generate_user_url ( "DELETE", $bucket, $object, $opt );
    }

    /**
     * 生成head_object的url
     * @param string $bucket (Required)
     * @param string $object (Required)
     * return false| string url
     */
    public function generate_head_object_url($bucket, $object, $opt = array()) {
        $this->assertParameterArray ( $opt );
        return $this->generate_user_url ( "HEAD", $bucket, $object, $opt );
    }

    /**
     * @return the $use_ssl
     */
    public function getUse_ssl() {
        return $this->use_ssl;
    }

    /**
     * @param boolean $use_ssl
     */
    public function setUse_ssl($use_ssl) {
        $this->use_ssl = $use_ssl;
    }

    /**
     * 校验bucket是否合法，bucket规范
     * 1. 由小写字母，数字和横线'-'组成，长度为6~63位
     * 2. 不能以数字作为Bucket开头
     * 3. 不能以'-'作为Bucket的开头或者结尾
     * @param string $bucket
     * @return boolean
     */
    public static function validate_bucket($bucket) {
        //bucket 正则
        $pattern1 = '/^[a-z][-a-z0-9]{4,61}[a-z0-9]$/';
        if (! preg_match ( $pattern1, $bucket )) {
            return false;
        }
        return true;
    }

    /**
     * 校验object是否合法，object命名规范
     * 1. object必须以'/'开头
     * @param string $object
     * @return boolean
     */
    public static function validate_object($object) {
        $pattern = '/^\//';
        if (empty ( $object ) || ! preg_match ( $pattern, $object )) {
            return false;
        }
        return true;
    }

    /**
     * 将常用set http-header的动作抽离出来
     * @param string $header
     * @param string $value
     * @param array $opt
     * @throws BCS_Exception
     * @return void
     */
    private static function set_header_into_opt($header, $value, &$opt) {
        if (isset ( $opt [self::HEADERS] )) {
            if (! is_array ( $opt [self::HEADERS] )) {
                trigger_error ( 'Invalid $opt[\'headers\'], please check.' );
                throw new BCS_Exception ( 'Invalid $opt[\'headers\'], please check.', - 1 );
            }
        } else {
            $opt [self::HEADERS] = array ();
        }
        $opt [self::HEADERS] [$header] = $value;
    }

    /**
     * 使用特定function对数组中所有元素做处理
     * @param string    &$array        要处理的字符串
     * @param string    $function    要执行的函数
     * @param boolean   $apply_to_keys_also     是否也应用到key上
     */
    private static function array_recursive(&$array, $function, $apply_to_keys_also = false) {
        foreach ( $array as $key => $value ) {
            if (is_array ( $value )) {
                self::array_recursive ( $array [$key], $function, $apply_to_keys_also );
            } else {
                $array [$key] = $function ( $value );
            }

            if ($apply_to_keys_also && is_string ( $key )) {
                $new_key = $function ( $key );
                if ($new_key != $key) {
                    $array [$new_key] = $array [$key];
                    unset ( $array [$key] );
                }
            }
        }
    }

    /**
     * 由数组构造json字符串，增加了一些特殊处理以支持特殊字符和不同编码的中文
     * @param array $array
     */
    private static function array_to_json($array) {
        if (! is_array ( $array )) {
            throw new BCS_Exception ( "Param must be array in function array_to_json()", - 1 );
        }
        self::array_recursive ( $array, 'addslashes', false );
        self::array_recursive ( $array, 'rawurlencode', false );
        return rawurldecode ( json_encode ( $array ) );
    }

    /**
     * 根据用户传入的acl，进行相应的处理
     * (1).设置详细json格式的acl；
     * a. $acl 为json的array
     * b. $acl 为json的string
     * (2).通过acl_type字段进行设置
     * @param string|array $acl
     * @throws BCS_Exception
     * @return array
     */
    private function analyze_user_acl($acl) {
        $result = array ();
        if (is_array ( $acl )) {
            //(1).a
            $result ['content'] = $this->check_user_acl ( $acl );
        } else if (is_string ( $acl )) {
            if (in_array ( $acl, self::$ACL_TYPES )) {
                //(2).a
                $result ["headers"] = array (
                        "x-bs-acl" => $acl );
            } else {
                //(1).b
                $result ['content'] = $acl;
            }
        } else {
            throw new BCS_Exception ( "Invalid acl.", - 1 );
        }
        return $result;
    }

    /**
     * 生成签名
     * @param array $opt
     * @return boolean|string
     */
    private function format_signature($opt) {
        $flags = "";
        $content = '';
        if (! isset ( $opt [self::AK] ) || ! isset ( $opt [self::SK] )) {
            trigger_error ( 'ak or sk is not in the array when create factor!' );
            return false;
        }
        if (isset ( $opt [self::BUCKET] ) && isset ( $opt [self::METHOD] ) && isset ( $opt [self::OBJECT] )) {
            $flags .= 'MBO';
            $content .= "Method=" . $opt [self::METHOD] . "\n"; //method
            $content .= "Bucket=" . $opt [self::BUCKET] . "\n"; //bucket
            $content .= "Object=" . self::trimUrl ( $opt [self::OBJECT] ) . "\n"; //object
        } else {
            trigger_error ( 'bucket、method and object cann`t be NULL!' );
            return false;
        }
        if (isset ( $opt ['ip'] )) {
            $flags .= 'I';
            $content .= "Ip=" . $opt ['ip'] . "\n";
        }
        if (isset ( $opt ['time'] )) {
            $flags .= 'T';
            $content .= "Time=" . $opt ['time'] . "\n";
        }
        if (isset ( $opt ['size'] )) {
            $flags .= 'S';
            $content .= "Size=" . $opt ['size'] . "\n";
        }
        $content = $flags . "\n" . $content;
        $sign = base64_encode ( hash_hmac ( 'sha1', $content, $opt [self::SK], true ) );
        return 'sign=' . $flags . ':' . $opt [self::AK] . ':' . urlencode ( $sign );
    }

    /**
     * 检查用户输入的acl array是否合法，并转为json
     * @param array $acl
     * @throws BCS_Exception
     * @return string acl-json
     */
    private function check_user_acl($acl) {
        if (! is_array ( $acl )) {
            throw new BCS_Exception ( "Invalid acl array" );
        }
        foreach ( $acl ['statements'] as $key => $statement ) {
            // user resource action effect must in statement
            if (! isset ( $statement ['user'] ) || ! isset ( $statement ['resource'] ) || ! isset ( $statement ['action'] ) || ! isset ( $statement ['effect'] )) {
                throw new BCS_Exception ( 'Param miss: format acl error, please check your param!' );
            }
            if (! is_array ( $statement ['user'] ) || ! is_array ( $statement ['resource'] )) {
                throw new BCS_Exception ( 'Param error: user or resource must be array, please check your param!' );
            }
            if (! is_array ( $statement ['action'] ) || ! count ( array_diff ( $statement ['action'], self::$ACL_ACTIONS ) ) == 0) {
                throw new BCS_Exception ( 'Param error: action, please check your param!' );
            }
            if (! in_array ( $statement ['effect'], self::$ACL_EFFECTS )) {
                throw new BCS_Exception ( 'Param error: effect, please check your param!' );
            }
            if (isset ( $statement ['time'] )) {
                if (! is_array ( $statement ['time'] )) {
                    throw new BCS_Exception ( 'Param error: time, please check your param!' );
                }
            }
        }

        return self::array_to_json ( $acl );
    }

    /**
     * 构造url
     * @param array $opt
     * @return boolean|string
     */
    private function format_url($opt) {
        $sign = $this->format_signature ( $opt );
        if ($sign === false) {
            trigger_error ( "Format signature failed, please check!" );
            return false;
        }
        $opt ['sign'] = $sign;
        $url = "";
        $url .= $this->use_ssl ? 'https://' : 'http://';
        $url .= $this->hostname;
        $url .= '/' . $opt [self::BUCKET];
        if (isset ( $opt [self::OBJECT] ) && '/' !== $opt [self::OBJECT]) {
            $url .= "/" . rawurlencode ( $opt [self::OBJECT] );
        }
        $url .= '?' . $sign;
        if (isset ( $opt [self::QUERY_STRING] )) {
            foreach ( $opt [self::QUERY_STRING] as $key => $value ) {
                $url .= '&' . $key . '=' . $value;
            }
        }
        return $url;
    }

    /**
     * 将url中 '//' 替换为  '/'
     * @param $url
     * @return string
     */
    public static function trimUrl($url) {
        $result = str_replace ( "//", "/", $url );
        while ( $result !== $url ) {
            $url = $result;
            $result = str_replace ( "//", "/", $url );
        }
        return $result;
    }

    /**
     * 获取传入目录的文件列表
     * @param string $dir 文件目录
     * @return array 文件树
     */
    public static function get_filetree($dir, $file_prefix = "/*") {
        $tree = array ();
        foreach ( glob ( $dir . $file_prefix ) as $single ) {
            if (is_dir ( $single )) {
                $tree = array_merge ( $tree, self::get_filetree ( $single ) );
            } else {
                $tree [] = $single;
            }
        }
        return $tree;
    }

    /**
     * 内置的日志函数，可以根据用户传入的log函数，进行日志输出
     * @param string $log
     * @param array $opt
     */
    public function log($log, $opt) {
        if (isset ( $opt [self::IMPORT_BCS_LOG_METHOD] ) && function_exists ( $opt [self::IMPORT_BCS_LOG_METHOD] )) {
            $opt [self::IMPORT_BCS_LOG_METHOD] ( $log );
        } else {
            trigger_error ( $log );
        }
    }

    /**
     * make sure $opt is an array
     * @param $opt
     */
    private function assertParameterArray($opt) {
        if (! is_array ( $opt )) {
            throw new BCS_Exception ( 'Parameter must be array, please check!', - 1 );
        }
    }
}
